Battery packs (energy storage packs) that include a plurality of battery modules (energy storage apparatuses) housed in a pack case are well known. The plurality of battery modules each include one or more battery cells (energy storage devices) housed in a module case (for example, see Japanese Unexamined Patent Application Publication No. 2012-128983). In this sort of battery pack, in order to monitor, for example, the voltage of the battery cells, a cable for obtaining the voltage information is wired from an electrode terminal of the battery cell to outside the pack case of the battery pack.